Provided is a barium titanate production method which can produce a barium titanate powder of high tetragonal crystallinity, despite having a fine particle size of 80-150 nm, so as to be capable of accommodating reductions in the thickness of elements, such as laminated ceramic capacitors. A slurry is created by dispersing a barium titanate powder of finer particles than the ultimately produced barium titanate powder in a solvent such as ethanol, for example. Then, the barium titanate powder is separated by vaporising the solvent while pressurising the slurry in a pressure vessel (18) of a production device (10). Then, the separated barium titanate powder is heat treated. As a result, the barium titanate powder is produced.